Albur

Albur
 

I think it means piropo with an especially sexual connotation, but dictionaries say it has to do with chance. Is this term a regionalism?

It may mean both things.
- No se deja nada al albur. (Nothing must be left to chance.)
- Juego de albures (is a specific game of chance)
- Juan es bueno para jugar al albur. (Juan is good at playing that game of chance.)

In Mexico, it's a play on words with a strong sexual connotation. "Albures" are vulgar and aggressive, and they're definitely not piropos, even if some men try to present them as such.
- No quiero hablar con Pedro, porque a todo le encuentra el albur.
-> Pedro twists anything you say into a sexually charged sentence.
- Últimamente mucha gente en la televisión dice albures y nadie les dice nada.
-> On TV it's more and more common to hear people talking with double meaning and it's more and more tolerated.

Thank you. It can mean azar as well as a double entendre.

Yes, I'd like to emphasize only that it's a specific kind of double entendre, and as such it's very low register (not the word "albur" itself, but the practice of that kind of language).